The present invention relates generally to hinged folding mechanisms, and more specifically to hinged folding apparatus for attaching, lifting, supporting and unfolding an expandable top on a camper body.
Recreational camping vehicles in a variety of designs and forms are used widely by persons who desire convenient yet mobile camping facilities. Such vehicles include camper trailers, vans, and camper bodies mounted in pick-up truck boxes as well as camper bodies integrally attached to popular four-wheel drive vehicles. Since sufficient head room is required to accommodate persons standing in the camper bodies as well as to provide sufficient usable open space in the interior of the camper body, conventional camper bodies are relatively high and extend a considerable distance above the body of the vehicle on which they are mounted or by which they are being towed. This necessary height causes undesirable bulkiness, and even more significant, undesirable wind resistance while traveling at high speeds.
To overcome some of these problems during transportation, while providing the necessary height of the interior ceiling while in use for camping, camper bodies with expandable tops have been developed and are becoming more popular. Such camper bodies usually include a floor and lower portions of front, rear and side walls which are solid and substantially resemble conventional camper bodies. However, the height of the walls usually approximates the height of the vehicle on which the camper body is mounted. A top or roof panel is positioned over the walls. Front, rear and sidewall extensions are then provided by sheets of flexible fabric attached to the top of the solid wall sections and to the underside of the roof structure. A foldable support structure is then provided to support the roof panel a spaced distance above the solid wall sections for camping use and to allow the roof panel to be folded downwardly to rest directly on the top of the wall panels for transportation.
Such expandable tops are quite successful in solving the problem of excess wind resistance and bulkiness during transportation while providing sufficient head room in the interior of the camper as it is being used for camping. However, the foldable support structures and associated facilities for supporting the roof panel in a safe, stable manner, yet which can be easily operated with a minimum of time and effort to move the roof from the transportation position to its expanded position and refolding it again, have not been entirely satisfactory. Some of such folding mechanisms are somewhat unstable during the folding process, and time consuming measures and efforts must be made to keep the flexible fabric neatly folded out of the way to avoid wrinkling and pinching between the top and the upper wall sections, which if not avoided would ultimately result in tears and holes worn through the fabric thus impairing its effectiveness as a shelter. Bifold panels, particularly unbiased panels, have been in use in the public domain for foldably supporting roofs on camper bodies, however, it has been found that improvements are desirable to increase their utility and effectiveness for such use.